# Detect tampered and deepfake Vaccination Certificate > A fake vaccination certificate is identified either by verifying its QR code or, where the certificate is paper only, by reading the printed record against itself. A valid digital certificate carries a cryptographic signature over the holder's identity and dose data, so any change to the printed page breaks agreement with the payload the code encodes. Without a code, the work falls to the batch numbers, the interval between doses, and the issuing centre's stamp, which are the fields travel and employment checks turn on. **Canonical URL:** https://tampercheck.ai/documents-support/vaccination_certificate **API document class:** `vaccination_certificate` **Last updated:** 2026-10-07 --- ## What a genuine vaccination certificate contains An immunisation certificate records who was vaccinated, with what, and when. It names the holder and their date of birth, and where the scheme is tied to travel, a passport or national identity number. For each dose it gives the vaccine product name and manufacturer, the dose number in the series, the date administered, the batch or lot number, and the administering centre with its identifier and the clinician's name. The country of vaccination, the issuing authority's stamp or logo, and a 2D barcode encoding the same record complete the page. The dose entries are not independent. A second dose cannot be dated before a first, and vaccine schedules set a minimum interval between them, so dates moved to satisfy a deadline often close the gap below what the product allows. A batch number belongs to one manufacturer and one distribution window, which means a lot number cannot predate its own release or appear against a different product. Where a barcode is present it repeats the printed fields inside a signed payload, so page and payload have to match character for character. ## How vaccination certificate forgeries are made ### Dose date shifting Administration dates are moved so the holder appears to have completed a course before an entry window, a start date, or a policy deadline. The shift frequently leaves a gap between doses shorter than the product schedule permits, which makes the record invalid on its own terms regardless of the printing. ### Batch and lot number invention A plausible-looking lot number is written in, or one is copied from another certificate, because most reviewers have no way to check it on sight. Invented numbers commonly use the wrong format for the manufacturer, or pair a lot with a product or a date that lot was never distributed against. ### Holder identity substitution The name, date of birth, or passport number on a genuine certificate is replaced so one person's immunisation record covers another. On a certificate carrying a signed barcode this edit is self-defeating, because the payload still holds the original identity and no longer matches the page. ### QR code replacement The barcode is swapped for one that carries an unsigned payload, a payload signed by a key no issuer controls, or simply a URL dressed up to look like a verification link. A verifier app rejects all three, which is why the substitute code is usually paired with a page designed to discourage scanning. ### Issuing centre stamp and authority logo cloning The centre's stamp and the health authority's emblem are lifted from a real certificate and placed on another. Copied marks lose the ink variation and fibre bleed of a genuine impression and arrive as flat, uniformly bounded raster elements sitting above the page rather than in it. ### Certificates built from a scheme template The whole document is produced from a national or scheme layout, complete and internally consistent, with no barcode or a decorative one. Nothing here is an edit, so detection rests on generation signatures, on the print and scan characteristics of the page, and on whether the barcode verifies at all. ## What TamperCheck checks on a vaccination certificate TamperCheck runs 200+ forensic checks across three layers and returns a risk score from 0 to 100 with plain-English findings tied to specific regions of the document. These three carry the most weight on this document class. ### Stamp authenticity and placement Stamps are assessed for whether the ink was impressed onto the page or printed as part of it, and for whether the impression was placed digitally after the fact. ### Date and validity consistency Issue, expiry, and period dates are checked against one another and against the file's own creation metadata, which catches backdating and validity extension. ### Reference and document number checks Document, account, and reference numbers are checked for issuer format conformance and against every other place the same value appears on the page. ### And many more checks The three above are the layers that carry the most weight on a vaccination certificate. Every upload runs the full suite of 200+ checks regardless of document class, spanning file structure and metadata, pixel-level forensics, font and text rendering, optical and print characteristics, provenance signals, AI-generation signatures, and many more checks. ## Who verifies a vaccination certificate, and why Travel operators, employers, and health authorities confirming immunisation. In each case the document is being used to unlock money, access, or a legal status, which is exactly what makes it worth forging. ## How to verify a vaccination certificate in 4 steps 1. **Scan the code with an official verifier.** Use the issuing scheme's own verifier application rather than a general QR reader. A general reader will display whatever the code contains; a verifier checks the cryptographic signature against the issuer's published public key and tells you whether the payload is authentic and unrevoked. 2. **Compare the payload against the printed page.** Read the holder name, date of birth, vaccine product, dose dates and batch numbers out of the verified payload and compare them field by field with what is printed. A signed payload cannot be edited, so any divergence means the page was changed after issue. 3. **Check the dose interval and batch plausibility.** Confirm the gap between doses meets the minimum the product schedule sets, that dose numbers run in order, and that each batch number uses the manufacturer's format and is consistent with the date it was supposedly administered. 4. **Run a forensic check where there is no code.** Paper certificates with no barcode have to be judged on the document itself. TamperCheck runs 200+ forensic checks on the scan and returns a 0 to 100 risk score within seconds, naming the field, a dose date or a batch number, that carries evidence of editing. ## Frequently asked questions ### How do you detect a fake vaccination certificate? Scan the QR code with the issuing scheme's verifier app, which checks the payload's cryptographic signature and shows you the data as issued, then compare that data against what is printed on the page. Where there is no code, check the dose interval against the product schedule, the batch number format against the manufacturer, and the stamp and page for signs of editing. ### Can a vaccination QR code be forged? Not in the sense of producing a code that passes verification, because a valid certificate is signed with a private key held by the issuing authority and a verifier checks that signature. What forgers do instead is substitute a code that carries an unsigned payload or a link, which looks identical to the eye and fails the moment it is properly scanned. ### Do batch numbers matter when checking an immunisation record? Yes, they are one of the few fields on a paper certificate that can be independently sanity-checked. A lot number has a manufacturer-specific format and a distribution window, so a number in the wrong format, attached to a product that manufacturer does not make, or dated before that lot shipped, marks the record as fabricated. ### Can a printed vaccination certificate be verified without a QR code? It can be checked but not cryptographically verified, which is an important difference. Without a signed payload you are left with the document itself: interval and sequence logic across the doses, batch number plausibility, the issuing centre's identifier, and forensic analysis of the page to see whether the dates and names were printed in the same pass as everything around them. ## Related document types - Medical Certificate: https://tampercheck.ai/documents-support/medical_certificate - Medical Report: https://tampercheck.ai/documents-support/medical_report - Discharge Summary: https://tampercheck.ai/documents-support/discharge_summary - Lab Result: https://tampercheck.ai/documents-support/lab_result - Prescription: https://tampercheck.ai/documents-support/prescription - Health Insurance Card: https://tampercheck.ai/documents-support/health_insurance_card --- Try TamperCheck now: https://tampercheck.ai/dashboard · Docs: https://tampercheck.ai/docs · Pricing: https://tampercheck.ai/pricing